Temperature dependence of resonant frequency in optically excited diaphragms

Silicon diaphragms of 4 ¿m thickness, fabricated by anisotropic etching techniques, are coated with a thin layer of aluminium. An intensity-modulated laser beam focused on the diaphragm generates transverse vibrations which are detected interferometrically. The measured deflections, resonant frequencies and temperature dependence of resonant frequencies are reported.